A series or research studies are being conducted to determine the following: 1. The characteristics of vocal tic phenomena in Gilles de la Tourette Syndrome. 2. The differential effects of various neuropharmacological treatments on the type and severity of vocal tics in patients with Gilles de la Tourette Syndrome. 3. The relationship of vocal tic production to propositional language behavior and speech fluency. 4. Whether history of tics, Tourette Syndrome or stuttering in patients' family history are predictive of the vocal tic and language dysfunctions seen in patients with Tourette syndrome.